package com.atguigu.stuty.safe;

import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.UUID;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.CopyOnWriteArrayList;
import java.util.concurrent.CopyOnWriteArraySet;

/**
 * @Author early morning
 * @Create 2025/4/23 20:51
 * @Description:
 */
public class NotSafe {
    public static void main(String[] args) {
        Map<String,String> map = new ConcurrentHashMap<>();//new HashMap<>();

        map.put("1","张三");
        map.put("1","李四");

        System.out.println(map.size() +"\t"+ map.get("1"));
    }

    private static void mapNotSafe() {
        Map<String,String> map = new ConcurrentHashMap();//Collections.synchronizedMap(new HashMap<>());//new HashMap<>();

        for (int i = 1; i <=100; i++) {
            new Thread(() -> {
                map.put(Thread.currentThread().getName(), UUID.randomUUID().toString().substring(0,6));
                System.out.println(map);
            },String.valueOf(i)).start();
        }
    }

    private static void setNotSafe() {
        Set<String> set = new CopyOnWriteArraySet();//Collections.synchronizedSet(new HashSet<>());//new HashSet<>();

        for (int i = 1; i <=100; i++) {
            new Thread(() -> {
                set.add(UUID.randomUUID().toString().substring(0,6));
                System.out.println(set);
            },String.valueOf(i)).start();
        }
    }

    private static void listNotSafe() {
        // 读写分离，写时复制
        // Collections.synchronizedList(new ArrayList<>());//new Vector<>();//new ArrayList<>();
        List<String> list = new CopyOnWriteArrayList<>();

        for (int i = 1; i <=100; i++) {
            new Thread(() -> {
                list.add(UUID.randomUUID().toString().substring(0,6));
                System.out.println(list);
            },String.valueOf(i)).start();
        }
    }
}
